package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import com.itheima.reggie.entity.User;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求：{}",request.getRequestURI());

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/front/**",
                "/backend/**",
                "/backend/page/demo/upload.html",
                "/user/login",
                "/user/sendMsg"
        };

        //2.匹配路径
        boolean check = check(urls, requestURI);

        //不需要处理的直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request, response);
            return;
        }

        //已登录的直接放行
        if(request.getSession().getAttribute("employee")!=null){
            Long employeeId = (Long)request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(employeeId);
            log.info("用户已登录，用户id 为{}",employeeId);
            filterChain.doFilter(request, response);
            BaseContext.remove();
            return;
        }

        if(request.getSession().getAttribute("user")!=null){
            User user = (User)request.getSession().getAttribute("user");
            BaseContext.setCurrentId(user.getId());
            log.info("用户已登录，用户id 为{}",user.getId());
            filterChain.doFilter(request, response);
            BaseContext.remove();
            return;
        }

        //不允许进入，通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }

    /**
     * 路径匹配，检查本次请求是否放行
     * @param urls
     * @param requestURI
     * @return
     */
    public  boolean check(String[] urls,String requestURI){
        for(String url:urls){
            boolean match=PATH_MATCHER.match(url,requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
